The death toll continues to rise in southwestern Nigeria after more than a week of ethnic unrest. Several multinational oil companies have shut down their operations in the region, at a time when more oil is needed to make up for losses due to the war in Iraq.

It is impossible to say at this point how many people have been killed and wounded in more than a week of ethnic violence in southeastern Nigeria's Delta state. But indications are that scores, maybe even hundreds of people have died, with many more injured. At least 10 Nigerian soldiers are reported to be among the dead.

The Nigerian government has deployed roughly 1,000 troops to the Delta region to stem ethnic violence between the Ijaw and Itsekiri communities. But so far, the violence shows no signs of abating.

Itsekiri leaders say heavily armed Ijaw militants have burned at least 10 villages to the ground near the city of Warri. Hundreds of refugees have been streaming into Warri to escape the violence.

The Ijaws are demanding more autonomy from the federal government, and Ijaw community spokesmen say they will make the region ungovernable if their demands are not met.

Oil producing facilities have also been targeted in the unrest. The multinational oil companies Shell and ChevronTexaco have shut down all their operations in the region. They report a combined loss of 266,000 barrels per day, cutting Nigeria's overall oil production by just over 13 percent.

Both companies have evacuated most of their workers from the region. They have also airlifted hundreds of local villagers away from the violence.

Analysts fear the situation could deteriorate even further in the near future. A prolonged shutdown, combined with falling oil prices, could threaten Nigeria's economy, which is dominated by oil and gas revenues. Nigeria is the world's sixth-largest oil exporter, and the largest oil producer in Africa.

Oil prices have fluctuated wildly since the war began in Iraq, but overall prices have fallen by nearly $10 a barrel since last week. The oil cartel OPEC and the International Energy Agency say they are confident that OPEC can meet any shortfall that occurs because of the war.

There could be serious domestic repercussions for Nigeria. President Olusegun Obasanjo on Wednesday said the ethnic unrest in Delta state threatens next month's presidential and parliamentary elections. Other parts of the country have also experienced increasing politically related violence in the run-up to the poll. President Obasanjo says the level of violence Nigeria is currently experiencing is unacceptable.